The existing Bailey truss bridge along Hauser Bridge Road over South Fork Gualala River is located 1.19 miles southwesterly of the King Ridge Road/Tin Barn Road Intersection and 2.33 miles northeasterly of the Seaview Road/Kruse Ranch Road Intersection. The existing 12 foot wide steel truss bridge only allows for a single lane of traffic and is functionally obsolete. It is not feasible to rehabilitate the bridge to meet current design standards so it is replaced with a new bridge. The proposed bridge replacement is parallel to and downstream of the existing bridge. It provides for two 9-foot traffic lanes with two 2-foot shoulder for a 22-foot wide traveled way.

Based on visual impacts, neither a cast-in-place/prestressed box girder nor a composite steel girder alternative was acceptable to locals and users of the bridge. A steel arch was selected for this crossing because its cost is lower than an HSS truss alternative, and because it will be unopposed by locals and users of the bridge. The steel arch alternative was further developed to better conform to the site and to capture potential cost savings. The asymmetric arch configuration permits bridge construction without falsework in the river and a substructure that does not encroach on 100-year storm flows.

OPAC is the prime consultant for this project. In addition to project management and bridge structure design, OPAC coordinated the environmental studies with the County and preliminary engineering effort. Environmental work included Natural Environment Studies with a Biological Assessment, Northern Spotted Owl surveys, cultural resource assessment and technical coordination with USFWS.